Note: This bug is displayed in read-only format because the product is no longer active in Red Hat Bugzilla.

RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.

Bug 1731336

Summary:

svsematest command report error "Could not access /sys/kernel/debug/tracing/tracing_enabled"

Product:

Red Hat Enterprise Linux 8

Reporter:

Qiao Zhao <qzhao>

Component:

rt-tests

Assignee:

John Kacur <jkacur>

Status:

CLOSED ERRATA

QA Contact:

Chang Yin <cyin>

Severity:

unspecified

Docs Contact:

Priority:

unspecified

Version:

8.1

CC:

bhu, cyin, rt-maint

Target Milestone:

Flags:

pm-rhel: mirror+

Target Release:

---

Hardware:

Unspecified

OS:

Unspecified

Whiteboard:

Fixed In Version:

Doc Type:

If docs needed, set a value

Doc Text:

Story Points:

---

Clone Of:

Environment:

Last Closed:

2019-11-05 20:35:58 UTC

Type:

Bug

Regression:

---

Mount Type:

---

Documentation:

---

CRM:

Verified Versions:

Category:

---

oVirt Team:

---

RHEL 7.3 requirements from Atomic Host:

Cloudforms Team:

---

Target Upstream Version:

Embargoed:

Bug Depends On:

Bug Blocks:

1696402

Attachments:

Description	Flags
change tracing_enabled to tracing_on where needed	none

Description Qiao Zhao 2019-07-19 07:27:27 UTC

Description of problem:

Running rt-tests builtin command:
# svsematest -a -b 20us -f -i 100 -l 100 -S
#0: ID3174, P0, CPU0, I100; #1: ID3175, P0, CPU0, Cycles 100
#2: ID3176, P0, CPU1, I600; #3: ID3177, P0, CPU1, Cycles 13
#4: ID3178, P0, CPU2, I1100; #5: ID3179, P0, CPU2, Cycles 100
#6: ID3180, P0, CPU3, I1600; #7: ID3181, P0, CPU3, Cycles 74
#8: ID3182, P0, CPU4, I2100; #9: ID3183, P0, CPU4, Cycles 52
#10: ID3184, P0, CPU5, I2600; #11: ID3185, P0, CPU5, Cycles 7
#12: ID3186, P0, CPU6, I3100; #13: ID3187, P0, CPU6, Cycles 29
#14: ID3188, P0, CPU7, I3600; #15: ID3189, P0, CPU7, Cycles 22
#16: ID3190, P0, CPU8, I4100; #17: ID3191, P0, CPU8, Cycles 17
#18: ID3192, P0, CPU9, I4600; #19: ID3193, P0, CPU9, Cycles 13
#20: ID3194, P0, CPU10, I5100; #21: ID3195, P0, CPU10, Cycles 10
#22: ID3196, P0, CPU11, I5600; #23: ID3197, P0, CPU11, Cycles 7
#24: ID3198, P0, CPU12, I6100; #25: ID3199, P0, CPU12, Cycles 5
#26: ID3200, P0, CPU13, I6600; #27: ID3201, P0, CPU13, Cycles 3
#28: ID3202, P0, CPU14, I7100; #29: ID3203, P0, CPU14, Cycles 1
#30: ID3204, P0, CPU15, I7600; #31: ID3205, P0, CPU15, Cycles 0
#1 -> #0, Min    4, Cur    4, Avg    4, Max   17
#3 -> #2, Min    4, Cur   29, Avg    7, Max   29
Could not access /sys/kernel/debug/tracing/tracing_enabled
#5 -> #4, Min    4, Cur    5, Avg    4, Max   18
#7 -> #6, Min    4, Cur    5, Avg    4, Max   13
#9 -> #8, Min    4, Cur    4, Avg    5, Max   17
#11 -> #10, Min    4, Cur   26, Avg    9, Max   26
Could not access /sys/kernel/debug/tracing/tracing_enabled
#13 -> #12, Min    4, Cur    4, Avg    5, Max   16
#15 -> #14, Min    4, Cur    4, Avg    5, Max   13
#17 -> #16, Min    4, Cur    4, Avg    5, Max   18
#19 -> #18, Min    4, Cur    4, Avg    5, Max   13
#21 -> #20, Min    4, Cur    4, Avg    6, Max   17
#23 -> #22, Min    4, Cur    4, Avg    6, Max   14
#25 -> #24, Min    4, Cur    4, Avg    7, Max   17
#27 -> #26, Min    4, Cur    4, Avg    7, Max   14
#29 -> #28, Min   16, Cur   16, Avg   16, Max   16
#31 -> #30 (not yet ready)

Some error/msg show "Could not access /sys/kernel/debug/tracing/tracing_enabled"
Checked current tracing behavior, we use tracing_on to control enabled/disable.
EasyFix.

Version-Release number of selected component (if applicable):
kernel-rt-4.18.0-108.rt20.49.el8.x86_64
rt-tests-1.3-20.el8.x86_64

How reproducible:

Steps to Reproduce:
1.
2.
3.

Actual results:


Expected results:


Additional info:

Comment 1 Qiao Zhao 2019-07-19 07:53:38 UTC

I draft a patch and test passed. Please review.

For current RHEL7 and RHEL8, we use tracing_on to control tracing disable/enable.
The tracing_enabled is not the correct value.

diff --git a/src/svsematest/svsematest.c b/src/svsematest/svsematest.c
index dfa4660..a265d90 100644
--- a/src/svsematest/svsematest.c
+++ b/src/svsematest/svsematest.c
@@ -187,7 +187,7 @@ void *semathread(void *param)
                                char tracing_enabled_file[MAX_PATH];
 
                                strcpy(tracing_enabled_file, get_debugfileprefix());
-                               strcat(tracing_enabled_file, "tracing_enabled");
+                               strcat(tracing_enabled_file, "tracing_on");
                                int tracing_enabled =
                                    open(tracing_enabled_file, O_WRONLY);
                                if (tracing_enabled >= 0) {

Comment 2 John Kacur 2019-07-31 15:36:46 UTC

Created attachment 1595128 [details]
change tracing_enabled to tracing_on where needed

Comment 7 errata-xmlrpc 2019-11-05 20:35:58 UTC

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2019:3308